Petrova O. The lichen genus Usnea in eastern Gennoscandia. III Shrubby species. Ann. Bot. Fennici. 1999, 36, p. 235-256.

246 Halonen • ANN. BOT. FENNICI 36 (1999) Motyka (LBL!, holotype). Chemistry: usnic, norstictic, cryp- tostictic and stictic acids (TLC by P. Clerc). Usnea compacta Motyka ex de Lesdain, Ann. Crypt. Exot. 5: 123. 1932, nom. nud. — Usnea compacta Motyka, Usnea 1: 294. 1936. — Type: Poland. Tatra Mts., Ko s cie- liska valley, Sorbus , 1923 Motyka (LBL!). — This is tech- nically a new species with a type different from Usnea gla- brescens var. compacta Räsänen. [There are annotations on the type sheet, however, which indicate that the speci- men has been collected from Sweden, Örebro, 1908 (?) by Svedberg !]. Usnea glabrescens var. compacta Räsänen, Memoranda Soc. Fauna Fl. Fenn. 8: 188. 1933, as “(Motyka) Räsänen”. — Type: Finland. Keski-Pohjanmaa, Lappajärvi, Salmela, in saepe veteri, 1914 Nyström (H!, holotype?). Chemistry: usnic, salazinic, norstictic, connorstictic (trace) and stictic (trace) acids. Usnea betulina Motyka, Usnea 1: 297. 1936. — Type: Finland. Etelä-Häme, Hollola, Hersala, in Betula , 1873 Vainio (H-NYL 36522!, holotype; LBL!, isotype). Chem- istry: usnic, salazinic (trace) and norstictic acids. Usnea distincta Motyka, Usnea 1: 298. 1936, nom. illeg. ( non Usnea distincta Motyka ex Räsänen 1935). — Type: Russia. Republic of Karelia, Karelia ladogensis, Kurkijoki, Pieni Heposaari [“Pieni Heposou (?)”], 1925 Räsänen (LBL!, holotype; S-Motyka 206!, isotype). Chemistry: usnic, salazinic and norstictic acids (lectotype). Usnea extensa Vain. subsp. gemina Motyka, Usnea 1: 304. 1936.—Type: Norway. Sør-Trøndelag, Buvika, Picea , 1934 Degelius (LBL, holotype, n.v. ; UPS!, isotype). Chem- istry: usnic acid (isotype). — The isotype collection also contains a thallus of Usnea subfloridana with usnic and thamnolic acids. Usnea wasmuthii Räsänen var. subglabrescens Räsä- nen, Ann. Bot. Soc. Zool. Bot. Fenn. Vanamo 12(1): 51. 1939.—Type: Russia. Republic of Karelia, Karelia ladogen- sis, Kurkijoki, Otsanlahti, ad corticem alni, 1932 Räsänen (H!, lectotype, here designated). Chemistry: usnic, salazinic (trace) and norstictic acids. — Syntype: Russia. Republic of Karelia, Karelia ladogensis, Kurkijoki, Rahola, Kuoks- vuori, ad corticem Alni incanae , 1935 Räsänen . Chemis- try: usnic, salazinic, norstictic and connorstictic acids. Usnea similis (Motyka) Räsäsnen var. globigera Räsä- nen, Ann. Bot. Soc. Zool. Bot. Fenn. Vanamo 20(3): 7. 1944. — Type: Finland. Varsinais-Suomi, Nauvo, Pensar, ad ru- pem praeruptam, 1940 Auer (H!, holotype). Chemistry: us- nic, norstictic, cryptostictic and stictic acids. Usnea wasmuthii var. sphaeroidea Räsänen, Ann. Bot. Soc. Zool. Bot. Fenn. Vanamo 20(3): 7. 1944. — Type: Finland. Pohjois-Savo, Kuopio, Levänen, ad corticem Betu- lae , 1941 Räsänen (H!, holotype). Chemistry: usnic, sala- zinic, norstictic, connorstictic and stictic acids. Thallus (Fig. 5) at first erect, later becoming subpendent or rarely pendent, often relatively tall, to ca. 15(–25) cm long, rather sparsely or more rarely densely branched. Branching mostly iso- tomic-dichotomous. Branches slender to thick, to ca. 1.8(–2.5) mm in diam. Annular cracks com- mon, often with a thin, white medullary ring. Base distinctly blackened. Cortex usually relatively thick, 9– 11 –13% ( n = 30). Medulla relatively thin to relatively thick, 10– 17 –23% ( n = 30). Central axis generally relatively thick, 32– 43 –56% ( n = 30). Papillae usually low, abundant on main branches, but lacking or sparse on secondary branches. Fibrils rarely copious, generally sparsely present at basal parts and absent to sparse near apices. Soralia ( see Clerc 1987b: 101) usuallywide- ly spaced, rounded and flat, sometimes tubercu- late, later occasionally becoming ± excavate (es- pecially near apices) and locally confluent and/or irregular in shape; soredia farinose. Isidia rarely Fig. 5. Subpendent thallus of Usnea glabrescens (Nyl. ex Vain.) Vain. ex Räsänen with sparse fibrils. From 1964 Ulvinen (OULU). Scale = 1 cm